高速过滤在钢铁厂再生水回用处理中的应用研究

Application of high-speed filtration process in treatment of reclaimed water in iron and steel plant

高速过滤工艺已成为钢厂再生水回用处理的必要环节。考察了有效粒径d10为1.35 mm的粗粒径石英砂均质滤料过滤系统对浊度的处理效果,结果表明:投加适当的絮凝剂后,该高速过滤系统在15 m/h滤速下出水浊度小于或等于3 NTU,过滤周期大于48 h,满足钢铁企业再生水回用对浊度的要求,可实现工程应用。过滤系统最佳冲洗强度为:气冲17 L/(m2.s),水洗10 L/(m2.s),水漂洗19 L/(m2.s)。

The high-speed filtration process has become a necessary part of reclaimed water treatment in steel plant. The effect of filtration system using homogeneous filtering materials of coarse particle size silica sand with an effective size dl0 of 1.35 on turbidity removal was investigated. The results showed that, with the addition of proper floeculant, the turbidity of the effluent water from the said high-speed filtration system with a filtering velocity of 15 m/h was lower or equal to 3 NTU, the filtration cycle was longer than 48 h. It could be seen that, using high-speed filtration process to treat reclaimed water, the turbidity of the effluent water could meet the re- quirement of make-up water for iron and steel enterprises; therefore, the application of the said process in actual engineering was feasible. The optimal backwashing intensity of the filtration system was： the gas rate was 17 L/ （m2-s）, the water rate was 10 L/（m2.s）, the water rinsing rate was 19 L/（mE＇s）.